Mechanistic and evolutionary analysis of the natural variation in Arabidopsis vernalization response

要全面了解气候变化将如何影响植物，需要了解用于监测环境线索的机制如何随着植物适应不同的栖息地而发生变化。在温带和北极环境中，许多植物开花的调节包括需要一段时间的寒冷暴露，称为春化。在这个建议中，我们希望充分表征春化作用中自然变异的分子基础。这一过程的主要调节因子是FLC，一种花抑制因子。编码FLC的基因需要被沉默才能开花，并且在从不同栖息地收集的拟南芥中发生的速度不同。我们将分析FLC调节以及它如何演变以适应不同的气候。将在转基因植物中分析来自不同天然变体的FLC基因的“混合匹配”版本，以揭示不同核苷酸变化中的哪一个有助于改变春化反应。在与人口遗传学家Magnus Nordborg博士的合作中，我们将分析世界范围内拟南芥种质的FLC，并将序列变异与春化反应联系起来。我们还将进行实验，分析这种变化的健身效益，并将这些数据与两项平行研究中产生的田间表型数据进行比较。这将揭示是否在春化的变化是重要的适应。

A full understanding of how climate change will influence plants requires an understanding of how mechanisms used to monitor environmental cues have changed as plants have adapted to different habitats. Regulation of flowering in many plants in temperate and arctic environments includes a requirement for a period of exposure to cold, known as vernalization. In this proposal we want to fully characterize the molecular basis of natural variation in vernalization. A major regulator of this process is FLC, a floral repressor. The gene encoding FLC needs to be silenced for flowering to proceed and the speed this happens differs in Arabidopsis collected from different habitats. We will analyse FLC regulation and how it has evolved in response to adaptation to different climates. 'Mix-and-match' versions of FLC genes from the different natural variants will be analysed in transgenic plants to uncover which of the different nucleotide changes contributes to the altered vernalization response. In collaboration with Dr Magnus Nordborg, a population geneticist, we will then analyse FLC in a worldwide set of Arabidopsis accessions and relate sequence variation to vernalization response. We will also undertake experiments analysing the fitness benefits of this variation and compare these data to field-derived phenotypic data generated in two parallel studies. This will reveal whether variation in vernalization is important for adaptation.